package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否完成登录
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求:{}",requestURI);

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",//登录
                "/employee/logout",//登出
                "/backend/**",//请求静态资源
                "/front/**",//请求前端静态资源
                "/common/**",
                "/user/sendMsg",
                "/user/login",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };

        //2.判断本次请求是否需要处理
        boolean check = check(urls,requestURI);

        //3.如果不需要处理，则直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }



        //4.1 判断登录状态，如果已登录则直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);
            return;
        }

        //4.2 判断登录状态，如果已登录则直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已登录，用户id为:{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");
        //5.如果未登录则返回未登录结果，通过输出流的方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    public boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url,requestURI);
            if(match) return true;
        }
        return false;
    }
}
